Passenger Pigeons lived in the eastern United States
from Canada to the Gulf of Mexico, breeding in their northern habitats
and wintering in the southern part of their range. They migrated across
this range in numbers so huge that their flocks darkened the sky. A writer
once described a migrating flock of the pigeons as "a column, eight or
ten miles in length . . . resembling the windings of a vast and majestic
river." In 1808 a single flock in Kentucky was estimated to contain over
2 billion birds. Today, in a stunning example of the human potential for
destruction, the Passenger Pigeon is extinct.

During the years of westward expansion, enormous numbers
of eastern chestnut and oak trees, the main source of food for the Passenger
Pigeon, were cleared to make way for farms, homesteads, and towns. Moreover,
the birds were believed to be a menace to crops, while they seemed to be
an inexhaustible supply of food for both people and their pigs. With the
extension of the railroad in the 1850s, the pigeons could be easily shipped
to city markets, increasing the numbers in which they were hunted. The
combination of all these factors wiped out the Passenger Pigeon. The last
one, which lived in the Cincinnati Zoological Garden, died on September
1, 1914.